Exhaust valve for combustion engines

Abstract

An exhaust valve ( 10 ) includes a housing ( 44 ) having a passageway ( 46 ) extending axially therethrough. The exhaust valve ( 10 ) also includes a rotatable butterfly plate ( 50 ) disposed in the passageway ( 46 ) of the housing ( 44 ) and having an annular groove ( 52 ) in a periphery thereof. The exhaust valve ( 10 ) further includes a ring seal ( 60 ) disposed in the groove ( 52 ) and being radially compressible and expandable for engagement and disengagement with the housing for opening and closing the passageway ( 46 ) to allow and prevent exhaust gases flowing therethrough.

What is claimed is:  
     
       1. An exhaust valve for an exhaust heat recovery system of a motor vehicle comprising: 
       a housing for attachment to the exhaust heat recovery system of the motor vehicle and having a passageway extending axially therethrough;  
       a rotatable butterfly plate disposed in said passageway of said housing and having a plate portion with an annular groove axially within said plate and extending radially inwardly in a periphery thereof, said plate including a shaft portion extending outwardly from one side of said plate portion and having an aperture extending therethrough, a shaft extending through said aperture, said aperture being offset laterally from a longitudinal axis of said housing; and  
       a metal ring seal disposed in said groove and extending radially beyond the periphery of said plate and being radially compressible in said groove and radially expandable for engagement and disengagement with said housing for opening and closing said passageway to allow and prevent exhaust gases flowing therethrough.  
     
     
       2. An exhaust valve as set forth in  claim 1  wherein said plate portion is generally planar and circular in shape. 
     
     
       3. An exhaust valve as set forth in  claim 1  including means for securing said shaft to said shaft portion. 
     
     
       4. An exhaust valve as set forth in  claim 1  wherein said aperture is offset longitudinally from a plane extending through said groove. 
     
     
       5. An exhaust valve as set forth in  claim 1  wherein said housing has a pair of opposed apertures extending diametrically therethrough. 
     
     
       6. An exhaust valve as set forth in  claim 5  including a bushing disposed in each of said apertures, said shaft extending through said bushing and said apertures. 
     
     
       7. An exhaust valve as set forth in  claim 1  including means for preventing said ring seal from rotating along said groove. 
     
     
       8. An exhaust heat recovery system for a motor vehicle comprising: 
       an exhaust pipe for attachment to an exhaust system of the motor vehicle;  
       a heat exchanger disposed in parallel to said exhaust pipe and connected thereto;  
       a backpressure valve disposed between an exist end of said heat exchanger and said exhaust pipe;  
       an exhaust valve disposed between an entrance end and the exit end of said exhaust pipe; and  
       said exhaust valve comprising a housing for attachment to said exhaust pipe and having a passageway extending axially therethrough, a rotatable butterfly plate disposed in said passageway of said housing and having a plate portion with an annular groove axially within said plate and extending radially inward in a periphery thereof, and a ring seal disposed in said groove and extending radially beyond the periphery of said plate and being radially compressible in said groove and radially expandable for engagement and disengagement with said housing for opening and closing said passageway to allow and prevent exhaust gases flowing therethrough, said butterfly plate including a shaft portion having an aperture extending therethrough, a shaft extending through said aperture and engaging said housing, said aperture and shaft being offset laterally from a longitudinal axis of said housing.  
     
     
       9. The system of  claim 8  wherein the aperture and shaft are offset longitudinally from a plane extending through said groove.